Dunn is scheduled to make his first start of the season Wednesday against the Angels, Greg Johns of MLB.com reports.
As anticipated, Dunn will begin the season as the Mariners' sixth starter after manager Scott Servais decided to expand the rotation due to the compressed schedule in the 60-game campaign. The 24-year-old will likely have his workload managed more carefully than the Mariners' other rotation members, but he should be a decent source of strikeouts on a per-inning basis after whiffing 28.6 percent of his opposing hitters he faced at the Double-A level in 2019.